Hydraulically operated ratchet wrench



May 9, 1961 A. c. RASMUSSEN ETAL 2,983,172

HYDRAULICALLY OPERATED RATCHET WRENCH Filed Feb. 29, 1960 2 Sheets-Sheet 1 NV EN TOR.

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HYDRAULICALLY OPERATED RATCHET WRENCH 2 Sheets-Sheet 2 Filed Feb. 29, 1960 5 S 0 L 43 v 5 5 55551:; .l \/M\/ a 2 m s a 6 2 O 6 a 6 IIVVENTORJ 9%;

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United States Patent HYDRAULICALLY ornnxrnn RATCHET WRENCH Albert c. Rasmussen, 4010 Katherine St., and John L. Stroud, 531 s. 36th St, both of Phoenix, Ariz.

Filed Feb. 29, 1960, Ser. No. 11,910 2 Claims. (01. s1-ss.1

This device concerns improvements in ratchet wrenches having hydraulically operated ratchet operating mechamsm.

One of the objects of the device is to provide a ratchet wrench having a head with bosses adapted to receive other tools such asscrew bits or the like, which ratchet may be operated in the normal manner by swinging the handle, or maybe operated by a hydraulic pump positioned within the'handle.

Another object is to provide a ratchet wrench having means for carrying nut adapters which is constructed so that nuts maybe turned either by swinging the handle so that the ratchet operates progressively, or, if desired, the ratchet mechanism may be operated by hydraulic pump means positioned in the handle and operated by a hinged lever extending outward from the handle.

Other objects will appear hereinafter.

We attain the foregoing objects by means of the devices, construction, parts and combinations of parts shown in the accompanying drawings, in which- Figure l is a plan view of a wrench incorporating our improvements;

Figure 2 is a side view thereof;

Figure 3 is a mid-sectional plan view;

Figure 4 is a plan view of the inner face of the head cover plate.

Similar numerals refer to similar parts in the several views.

The wrench consists of a handle 2 which is cylindrical and has a head 3 on its outer end which contains the ratcheting mechanism and a pair of bearing ears 4 midway of the length of the handle to receive and pivotally hold the forward end of an operating lever 5. A boss 6 is positioned near the butt 7 of the handle which receives a plunger 8 attached to handle to operate a hydraulic pump 10 within the handle.

A second boss 12,protrudes from the opposite side of the handle from the boss 6 and forms the base and support for a relief valve 14 positioned within the handle.

The outer end of the handle adjacent the head, and marked 15, Figure 3, is bored to form a hydraulic cylinder 16. A piston 17 operates within this cylinder and has a piston rod 18 which operates through a gland 20 at the outer end of the cylinder. The head 3 is provided with a recess 21 wherein .the ratchet wheel 22 is operated and journalled on bearing bosses 23 at each end. These bosses form annular shoulders which constitute journals for ratchet wheel 22 and journal in bearing holes 27 in the base part 28 of the head 3 and in the cap part 29 of the head. The cap part 29 of the head 3 is secured to the base part by machine screws 29a. The base part of the head 3 is provided with a radially extending boss 24 which has a threaded portion 25 at its outer end. This threaded portion screws into an internally threaded portion 26 of the handle portion 15.

A central bore 30 within the handle communicates with a replaceable oil inlet valve 31 within the bore and bore, in turn, communicates with a reservoir inlet valve voir 33 in the butt end 34 of handle 2. The reservoir.

32. This second valve 32 opens into a cylindrical reseris closed at its outer end by a flexible diaphragm 35-of neoprene, or similar material, which is in the form of a disk. Its edges are gripped between a compressive washer 36 and an annular shoulder 36a. Screw plug 37, screwed into a threaded bore in the butt end 34 of the handle 2 compresses washer 36 and the rim of diaphragm onto shoulder 36a. Washer 36 has a central opening 38 which opens into a central bore 39 in plug 37.

At the outer end of piston rod 18 there is a pawl 40 which is hinged to the piston rod by a cross pin 41. The outer end 43 of the pawl is resiliently urged toward the periphery of the ratchet wheel 22 by a flat spring 42 so that the outer end of the pawl normally engages ratchet teeth 44 of the wheel. It is to be noted that centrally of the bearing boss shoulders 23 of the ratchet wheel 22 there are squared bosses 45. These are on both sides of the ratchet wheel, and are adapted to receive conventional nut adapters.

Pump 10 includes a piston 9 on piston rod 8 which is operated by lever 5 and which operates in cylinder 50 axial passageway 52 and with .the cylinder 16 through axial passageway 53. Operation of the handle 5 operates piston 9 as a pump and draws oil from reservoir 33 through valve 32 and forces it through the valve 31 and thence through the axial bore 30 and into cylinder 16. This forces the piston 17 forward so that pawl 40 engages the pawl teeth 44 and tends to rotate the ratchet wheel 22. A spring 55 surrounding piston rod 18 normally tends to return piston 17 to the inner end of cylinder 1-6.

To release oil under pressure from the inner end of cylinder 16.1 provide a passageway 57 which opens through a ball check valve 58 in boss 12, controlled by a butt, on release 60, into reservoir 33. When the check valve ball 58 is depressed by pin 61 on button shaft 62, oil will be released through eccentrically positioned passageway 64 into reservoir 33.

It will be observed that when the pump piston 9 is operated by action of lever 5, fluid is drawn out of chamber 33. To prevent air from being sucked into this chamber I provide the flexible diaphragm 35. As suction increases within chamber 33 the diaphragm flexes inwardly, as shown, and air enters through the openings 39 and 38. The chamber 33 is sealed from the outside air but when suction draws fluid from chamber 33, it will be displaced by the bulge of diaphragm 35, and air will not be drawn into chamber 33 orother parts of the interior of the handle.

In use the wrench is applied to a nut, or other object to be rotated by a suitable adapter temporarily attached to either of the squared bosses, as desired and the nut turned by swinging the handle 2 back and forth, to operate the ratchet, as with ordinary ratchet wrenches.

If there is not room to swing the handle then the pump grip handle 5 is operated and the pumping action attained through piston 9 and oil X contained within reservoir 33 will force ratchet wheel 22 to rotate. Intermittent ratchet motion may be had by forcing piston 17 outward and then releasing the pressure by pressing button' 60. Multiplication of power is attained by the difierence in diameter of pistons '17 and 9. With the handle properly held great rotative force can be brought to bear on the squared bosses 45.

The following claims define the breadth of our invention.

We claim:

1. In a hydraulically operated ratchet wrench, a head,

l atented May 9, 1961 a 3 a body having a cylindrical handle extending radially from said head, said head journalling a ratchet wheel with its axis at right angles to the extent of said handle, a piston rod, a pawl pivoted onsaid piston rod Within said-handle and having an outer end adapted to engage.

notches in said ratchet .wheel; said ratchet wheel, having peripheral .teeth and a shaft extending, outward through said head and journalled therein and provided with squared bosses to receive nut adapters, a power cylinder bore extending longitudinally within the inner end of said handle, adjacent said head, a piston operating within said cylinder bore carrying said piston rod'; means for pumping hydraulic fluid into said cylinder comprising a pump bore in said handle extending transversely relative to said handle bore, a piston operating in said pump bore, a lever hinged on outside of said handle body and pivotally connected to said pump piston; an axial bore in the outer end of said handle body forming a reservoir for hydraulic fluid; an inlet valve connecting said reservoir to said pump cylinder, an outlet valve connecting said pump cylinder to said cylinder in the inner end of said handle; a return passageway connecting said cylinder to said reservoir, a normally closed relief valve closing said passageway, a thumb button on said body handle adapted to open said relief valve, and a resilient displacement diaphragm secured in the outer end of said handle and closing said reservoir and arranged so that air will enter into said bore on the outer side of said diaphragm when fluid is drawn out of said reservoir and pumped into said power cylinder bore.

2. In av hydraulically operated ratchet wrench, a head, a body having a cylindrical handle extending radially from said head, said head journalling a ratchet wheel with its axis at right angles to the extent of said handle, a piston rod, a pawl pivoted on said piston rod within said handle and having an outer end adapted to engage notches in said ratchet wheel; said ratchet wheel having peripheral teeth and a shaft extending outward through said head and journalled therein and provided with squared bosses to receive nut adapters, a power cylinder bore extending longitudinally within the inner. end of said handle, adjacent said'head, a piston operatin-gwithin said cylinder bore carrying said piston rod; means for pumping hydraulic fluid into said cylinder and comprising a pump bore in said handle extending transversely relative to said handle bore, a piston operating in said pump bore, a lever hinged on outside of said handle body and pivotally connected to said pump piston; an axial bore in the outer end of said handle body forming a reservoir for hydraulic fluid; an inlet valve connecting said reservoir to said pump cylinder, an outlet valve-connecting said pump cylinder to said cylinder in the innerend of said handle; a return passageway connecting, said cylinder to said reservoir, a normally closed relief valve closing said passageway and a thumbbutton onsaid body handle adapted to open said relief valve.

References itedin the file of this patent 

